Printers are useful for producing printed images of a wide range of types. Printers print on receivers (or “imaging substrates”), such as pieces or sheets of paper or other planar media, glass, fabric, metal, or other objects. Printers typically operate using subtractive color: a substantially reflective receiver is overcoated image-wise with cyan (C), magenta (M), yellow (Y), black (K), and other colorants. Various schemes can be used to process images to be printed.
For example, commonly-assigned U.S. Publication No. 2008/0159786 by Tombs et al., entitled “SELECTIVE PRINTING OF RAISED INFORMATION BY ELECTROGRAPHY,” published Jul. 3, 2008, the disclosure of which is incorporated herein by reference, describes electrophotographic printing using marking particles of a substantially larger size than the standard size marking particles of the desired print image. Tombs et al. also describe using non-pigmented (“clear”) marking particles to overlay raised printing on an image. Using clear toners can improve image quality by reducing image relief artifacts with an inverse mask and providing a desired surface gloss. There is still, though, a continuing need for providing higher raised printing (e.g., thicker marking-particle stacks). Reference is also made to commonly-assigned U.S. Pat. No. 8,064,788 to Zaretsky et al., incorporated herein by reference.
Various schemes print patterns of yellow colorant as security features.